The long-term goal of this proposal is to expand and study our colony of nonhuman primates affected with Globoid Cell Leukodystrophy (Krabbe's disease). Nonhuman primates may be a critical step, before human trials, for evaluating the effectiveness and safety of novel therapies. This colony of rhesus monkeys represents the only colony of nonhuman primates in which an inherited lysosomal disorder has been recognized, propagated, and is available for study. In order for this unique animal model to be useful to the scientific community, the technologies to reliably produce a significant number of affected offspring must be in place, including the expansion of the size of the colony. The generation of large numbers of affected animals requires long-term support to expand this colony. The primary focus of this R24 grant is aimed at markedly improving the efficiency of producing macaques affected with Globoid Cell Leukodystrophy (GLD) through a stringent natural breeding program. Secondly, the pathogenesis of Krabbe disease will be analyzed in detail and utilized generate a database with the affected animals through molecular, biochemical, clinical, behavioral, and pathologic analyses. The proposed studies are critical for us to develop an extensive baseline of knowledge of disease progression in the nonhuman primate model, which, in the end, will be essential for the design and implementation of therapeutic interventions in the future. Lastly, one of the primary limitations of the GLD nonhuman primate model to date is unavailability of large numbers of affected animals. The limited number of GLD-affected animals has severely hampered our understanding of this disease model, but more importantly, the development and testing of therapeutic protocols. [unreadable] [unreadable] [unreadable]